Cat lovers will embrace this pretty tale of a pregnant stray who gives birth to kittens in the theater where impressionist painter Edgar Degas sketches dancers. The feline family is threatened by a huffy stage manager, but Degas stands up for them, even when they ruin his drawings. When the kittens interrupt a performance, however, it seems certain they'll be evicted--but the audience finds them charming, so they are saved. Sweeney's (Once Upon a Lily Pad) serviceable prose descends periodically into caricature (""Sacre bleu!"" cries the stage manager), and the character of Degas never comes into focus. She is similarly fuzzy with details (all of the dancers are called ballerinas, for example), and may thus disappoint ballet students. In her picture book debut, Wu makes the obvious choice of imitating the impressionist in hazy pastels but takes imaginative leaps with her perspectives (e.g., one playful picture shows the backs of the offstage kittens as they view the performing dancers)--and her kittens are undeniably adorable. A gatefold on the last page reproduces Degas's The Rehearsal on the Stage and invites readers to search for paw prints among the shadows. Ages 2-6. (May)